Abstract: Frequent route failures are common in a multipath internet protocol (IP) network. Backup configuration is one of the techniques used to re-establish alternate path in case of route failure. The existing multi route configurations (MRC) for fast IP network does not address quality of service (QoS) issues such as bandwidth optimisation and load balancing with traffic shaping. There is a need to focus on priority-based routing and load balancing during congestion in multipath networks. In this paper, we are proposing a priority-based bandwidth allocation and load balancing (PBALB) approach for multipath routing. In order to reduce packet drop and to enhance fairness, throughput and lower delay transmissions, traffic shaping based on different type of traffic flows in differential service domain is proposed. Experimental result shows that the proposed PBALB technique improves the throughput compared to MRC.